We cannot send mails signed with a X.509 certificate using the Zimbra Connector for Outlook 2007.
We have the following setup: The authentication is done through a third party directory service, and we are using the attribute “uid” (first letter of given name + last name, e.g. “jpublic” for “John Public“) for authentication. The Zimbra accounts are also named jpublic (resulting in firstname.lastname@example.org). We’ve then created several aliases for a user, e.g. email@example.com that are used for external communications.
Using IMAP or POP it’s not a problem to send a signed mail from firstname.lastname@example.org (the mail address the certificate is issued to). But some of our users are using the Outlook Connector, and although the Connector is configured to use the mail address email@example.com Outlook/the Connector tries to find a certificate for firstname.lastname@example.org (which doesn’t exist because in external communications we do not want to reveal our UIDs).
In the end Outlook/the Connector refuses to send signed mails from email@example.com, because it only looks for certificates issued to firstname.lastname@example.org. I think this is a problem of the Zimbra connector because it is possible to send signed mails from Outlook when using IMAP or POP3.
Do you have any suggestions how to solve this problem?